I find myself repeating this website address to people all the time. For almost every question writing related I utter the address. How do you find an agent? Agentquery.com How do you write a query letter? Agentquery.com. How do you format a novel for submission? Agentquery.com.
If you are breaking into the writing world either as a fiction or non-fiction writer, the website can answer all of your quesitons. I used it when I was sending out queries to agents and I still check in with the chats and to see what’s what in the writing world.